Cod sursa(job #1652173)

Utilizator razvandRazvan Dumitru razvand Data 14 martie 2016 19:08:10
Problema Fractii Scor 0
Compilator cpp Status done
Runda Arhiva de probleme Marime 0.59 kb
#include <iostream>
#include <fstream>

using namespace std;

ifstream in("fractii.in");
ofstream out("fractii.out");

long long getphi(long long nr) {
    long long cur = nr;
    for(long long i = 2;i * i <= nr; ++i)
    {
        if (nr % i == 0)
        {
            while(nr % i == 0)nr /= i;
            cur = (cur / i) * (i - 1);
        }
    }
    if (nr != 1) cur = cur / nr * (nr - 1);
    return cur;
}

int main() {
    int n = 10;
    long long s = 0;

    for(int i = 1; i <= n; i++) {

        s += getphi(i);

    }

    out << s*2-1;

    return 0;
}